Seismic Vulnerability Analysis Of Masonry Buildings

China is an earthquake-prone country,earthquake has caused heavy casualties and significant economic losses.The casualties and economic losses largely caused by the destruction of structures.Seismic fragility analysis has important theoretical and practical significance for structural seismic performence assessment,earthquake damage prediction,and post-earthquake damage assessment.Masonry structures have a long history,It has many advantages,such as simple structure,low cost,and it is widely used in China.The damage of buildings in earthquakes showed that masonry buildings which had been reasonably designed and strictly controlled the construction quality were able to meet the basic objective of seismic fortification.Some buildings kept standing even subjected to earthquake beyond their design intensity.For most small cities and towns of our country,masonry structures will still be widely used.Seismic fragility analysis of masonry buildings can provide basic data for earthquake damage prediction and post-earthquake loss assessment.In order to research fully on seismic vulnerability analysis of masonry buildings, the following work is carried out in this paper:1.An overview of the research process of seismic vulnerability study of the structures at home and abroad is delivered.2.The common methods for seismic vulnerability analysis of masonry structures are summarized.Based on damage data of masonry buildings collected from the previous Xinjiang earthquakes,the main failure characteristics are analyzed, its damage ratio is added up and the incomplete damage matrices are complemented.3.The influence of some design parameters such as mortar strength, building layers and floor height on the seismic vulnerability of masonry structures is discussed. Typical examples of designed multistory brick buildings and multistory brick buildings without design are selected and analyzed.4.The differences in construction and seismic vulnerability between constrained masonry buildings and normal designed masonry buildings are compared.5.The influence of the wall area ratio on the seismic vulnerability of masonry structures is probed.The minimum wall area ratio to meet the shear strength is provided. Then a vulnerability discrimination indicator based on masonry wall area ratio is presented and its reliability and availability are verified.